Dear 

Thank you for your letter, which arrived yesterday. As I’m sure you can imagine, we (1) have been very busy recently, having just moved into our new house. We are slowly settling in, although it (2) will be a long time before everything is finished. (friend) is putting down the living room carpet at the moment, and tonight we (3) are having a house-warming party. I was sorry to hear you couldn’t come. If we had told you earlier, you (4) could have put off your mother's visit. You said in your letter that you’d like to visit us in the summer. I’m sure we (5) will have finished all the things we want to do in the house by then. We (6) have seen exactly the kind of carpet we want to put upstairs, and we are going to buy it tomorrow.

Keep in touch. Give our regards to ...